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Criminal Liability: For Clients

Liability Under State and Local Law

Marijuana DUIs in California: Scientific and Legal Limbo

11/13/2017
By Ryan Kocot, Law Office of Ryan T. Kocot

The jury is still out on marijuana’s impact on one’s ability to drive, but one thing is for certain: cannabis DUI charges are becoming more and more common in California. This does not mean prosecutors are getting convictions, however. This article lays out the difficulties in prosecuting a marijuana DUI, and where the law is likely headed.

How Marijuana DUIs are Charged

Alcohol DUIs are typically charged under VC 23152(a) and VC 23152(b). VC 23512(b) is the section that everyone is familiar with: you cannot drive with a BAC at or above .08%. People are less familiar with VC 23152(a), however, so let’s look at it a little more closely. VC 23152(a) states that one cannot drive “under the influence.” To prove that someone was “under the influence” at the time they drove, prosecutors must prove that the individual could not drive with the caution of a sober person under similar circumstances.

So, what does this have to do with marijuana DUIs? Marijuana DUIs are charged under a different vehicle code section: VC 23152(f). However, this section asks the same question as VC 23152(a):

Was the individual driving “under the influence”?

As you can see, there is no “Per Se” limit for marijuana contained in VC 23152(f) like the .08% limitation contained in VC 23152(b).

The Two Main Problems with Prosecuting Cannabis DUIs

1. The blood test does not tell us much

A blood test is typically administered after someone is arrested on suspicion of a marijuana DUI. The blood test produces three different THC results, but only one of the results (the “Delta-9 THC”) provides any indication of whether a suspect would experience a “psychoactive” effect. Even then, the Delta-9 THC result does not take into consideration the suspect’s tolerance or lack of tolerance for cannabis. In a case where the suspect is pulled over for expired registration tags, or even speeding, how is the District Attorney to prove the suspect was “under the influence”? Proving that someone could not drive with the caution of a sober person becomes difficult when their driving pattern does not indicate impairment, or when they admit to regularly ingesting marijuana.

2. THC is Fat Soluble

The key distinction between marijuana and alcohol is at the crux of why prosecuting cannabis DUIs is difficult: the THC contained in marijuana is fat soluble, whereas alcohol is water soluble. Forensic toxicology provides a general idea of how long it takes alcohol to leave the system (generally .015–.03% per hour), but THC can stay in the system for weeks because it is stored in fat. This creates headaches for prosecutors up and down the state who have to prove that a defendant was under the influence at the time they drove.

Why don’t we have a “Per Se” Cannabis DUI limit in California?

The answer to this question could probably constitute an article of its own, but marijuana’s status as an illegal substance under Federal Law has played a large role. Without federal funding, we have a limited universe of scientific literature on marijuana’s impact on the ability to drive. Without that knowledge, it’s problematic to pass a law which states that “X” amount of THC renders an individual too impaired to drive. However, that has not stopped other states from adopting Per Se limits, usually set at either 2.5 ng/Ml or 5.0 ng/Ml of THC.

How Marijuana DUIs are Investigated: Drug Recognition Experts

Individuals under the influence of marijuana do not present the same “clues” that they are intoxicated as someone under the influence of alcohol. For example, a common field sobriety test administered during alcohol DUI investigations is called the Horizontal Gaze Nystagmus (HGN) field sobriety test. In short, the officer looks for involuntary jerking of the suspect’s eye, or “nystagmus,” as the suspect tracks a stimulus from side to side with their eyes. If the officer observes nystagmus, it is considered to be an indication or “clue” that the suspect is under the influence of alcohol. However, the HGN test has not been shown to indicate marijuana consumption or impairment. In fact, none of the field sobriety tests currently used in marijuana DUI investigations have ever been scientifically validated to be a reliable indicator of marijuana consumption and/or impairment.

In response to the faults in using traditional alcohol DUI investigatory techniques in cannabis DUI investigations, police departments have developed specialized training. Officers can be trained to become “Drug Recognition Experts” or DREs. During DRE training, officers are taught to perform a twelve-step follow-up investigation at the police station in addition to a blood test after a suspect is arrested to determine if the suspect is under the influence of cannabis.

Where Things are Headed

There have been rumblings of the creation of a marijuana breathalyzer, but the efficacy of such a test remains unclear due to THC being fat soluble and the lack of a “Per Se” limit in California. Interestingly, because there is no “Per Se” limitation, DMVs across California do not unilaterally take any administrative action if alcohol is not involved. However, a license suspension may be triggered if a defendant is convicted of a first or multiple marijuana DUI in criminal court. This may all change in the future, but until there is sufficient funding to adequately study marijuana, we will likely be stuck in scientific and legal limbo.

Ryan Kocot is the owner/operator of the Law Office of Ryan T. Kocot. His office is located in Sacramento, CA, but he practices all throughout Northern California. His practice focuses on criminal defence, as well as ensuring that cannabis cultivators, manufacturers, distributors, and retailers stay in strict compliance with state and local law.